Question

A 0.060 m piston initially contains air at 100 kPa and 10 oC. The air is then compressed adiabatically until the pressure is 600kPa. i. What is the mass of air inside the piston? i. What is the final temperature in the piston? ii. How much work is done during the compression? iv. What is the change in intemal energy of the air? v. What is the change in enthalpy of the air?

Note: Air is diatomic.

Please I need a clearly written, well solved and explanatory solution. I have had misleading solutions in the past which was really annoying. I appreciate a question left unsolved than a misleading solution. Please do not attempt if you are not sure that you can solve it. Thanks

Answer 1

Given that P = 100 kPa T,-10° C P = 600 kPa i)From the ideal gas equation, РУ 100x103 0.06 -2.55 moles RT8.314x283 For dry air, the molar mass is around 29 g/mol Hence the mass of the air m 29% 2.55-73.95 gram (ii) Applying adiabatic condition. For diatomic gas, γ (100)--x( 283)-= (600)_3xTỊ x (283)s T,-472.188 K= 199.188°C (ii)The work done in adiabatic process is given by nR 2.55×8.314 2 (283-472188) = W- -10027.295.J iv) Change in internal energy in adiabatic process is AQ-0 ALJ 10027.295 J